Mercury's surface in "enhanced color," a color scheme created to emphasize color differences. This is not what Mercury would look like to the human eye, but by applying mathematical analysis to images, color differences can be accentuated beyond those visible to a person.
Mount Rushmore National Memorial under construction.
The workers had to endure conditions that varied from blazing hot to bitterly cold and windy. Each day they climbed 700 stairs to the top of the mountain to punch-in on the time clock. Then 3/8 inch thick steel cables lowered them over the front of the 500-foot face of the mountain in a "bosun chair." Despite the dangers, no one was killed during the project.
Otters in Glacier Bay National Park and Preserve, Alaska.
The sea otter population of Glacier Bay has increased dramatically in the past 20 years. Ecologists consider sea otters a keystone species here. Otters consume vast quantities of clams, urchins, crabs, and other invertebrates and their presence creates ripples through the ecosystem. NPS photo.
Every day someone like you becomes a wildland wildfire fighter, a teacher, a trail-builder, a museum curator, or a park ranger. Discover your opportunities in national parks. Come to play. Come to learn. Come to serve. Develop your environmental leadership skills. Find a job. Be the next generation to preserve and protect these great places.
With more than 80% of Americans living in urban areas, urban parks are more important than ever. The father of American landscape architecture, Frederick Law Olmsted, said of urban parks:
It is one great purpose of the Park to supply to the hundreds of thousands of tired workers, who have no opportunity to spend their summers in the country, a specimen of God's handiwork that shall be to them, inexpensively, what a month or two in the White Mountains or the Adirondacks is, at great cost, to those in easier circumstances.
Washington, D.C.- “US Topo” is the next generation of topographic maps from the U.S. Geological Survey. Digital US Topo maps are designed to look, feel, and perform like the traditional paper topographic maps for which the USGS is so well known. However, in contrast to paper-based maps, US Topo maps provide technical advantages that support faster, wider public distribution and enable basic, on-screen geographic analysis for all users.
“The public's high regard for USGS topographic maps stretches over a century,” said Secretary of the Interior Ken Salazar. “Because Survey maps consistently describe our nation's entire landscape, they are the standard mapping reference for scientists, land managers, property owners, and every variety of outdoor enthusiast.”
“So I am very pleased,” continued Secretary Salazar, “that this new type of USGS topographic map not only preserves the best qualities of older topographic maps but now, in a popular digital format, can better serve both specialized users and the general public.”
Arranged in the familiar 7.5-minute quadrangle format, US Topo maps are available free on the Web. Each map quadrangle is constructed in GeoPDF® format from key layers of geographic data — orthoimagery, roads, geographic names, topographic contours, and hydrographic features — found in The National Map, a nationwide collection of integrated data from local, state, federal, and other sources.
“The USGS has always been at the forefront of new mapping technologies, but what distinguishes US Topo is the new methodology for delivering the product to users from all walks of life,” said USGS Director Marcia McNutt. “These digital maps can be as simple or as sophisticated as the need dictates, easily customized on the spot.”
US Topo users can turn geographic data layers on and off as needed, zoom in and out to highlight specific features or see a broader context, and print the maps — in their entirety or in customized sections — on a wide variety of printing devices. File size for each digital US Topo 7.5-minute quadrangle, about 15-20 megabytes, is convenient for most computer users. Electronic analytical tools are also available for free download.
“Everyone who learns about this new kind of USGS topographic map immediately wants to know how it compares to other electronic maps available on the Internet,” said Mark DeMulder, Chief of the USGS National Geospatial Program. “Here is how US Topo differs from most other electronic maps:
· Nationally consistent data quality assured to high standards
· Looks and feels like legacy paper USGS topographic maps but has technical advantages
The prototype of US Topo, Digital Map – Beta, has been available since June 2009. A US Topo map includes all of the content of the earlier Digital Map – Beta plus integrated contours and hydrographic features. As the US Topo product evolves, the USGS will provide digital, historical versions of USGS topographic map quadrangles and will incorporate additional geographic data layers from The National Map.